Printing device fob colobee- s llms



PRINTING DEVICE FOR COLORED FILMS Filed Hairch 28, 1929 was Patented July 28, 1931 UNITED STATES PATENT OFFICE BODOLIPHE BERTHON, OF NEUILLY, FRANCE, ASSIGNOR, BY MESNE ASSIGNMENTS, TO

KISLYN CORPORATION, OF NEW YORK,

N. Y., A CORPORATION OF DELAWARE PRINTING DEVICE FOR, COLORED FILMS Application filed March 28, 1929, Serial No. 350,623, and in France April 12, 1928.

In French Patent No. 622,996, granted to Rodolphe Berthon February 11, 1926, various processes are described which enable the removal of the network of the original film to be obtained by printing reticulated film, while projected, thus avoiding water lines in the reproduction; and among those possible, mechanical ones are included.

This invention has for its object a most effective electromechanical process which is easily adjustable and may be applied to any machine for the printing of reticulated films, even those which are provided with diaphragms for the elimination of such rays or beams as are diffracted by the network of the original film.

it is well known that such difiracted rays are the cause of water lines, and that their position in space for a given projection beam depends only on the position of the original network with respect to the optical center of the projecting lens. It follows that, primarily, it is merely necessary to shift said optical center with respect to the network by an amount equal to half an interval between two corrugations (or between two lines of the same color) to spread out each monochromatic striation over the whole surface corresponding to three consecutive monochromatic striations, and to completely remove the water lines produced by the optical superimposition of the original network with the reproduction network. Inasmuch as the pitch is of the order of to the millimeter, the necessary displacement will not exceed 1/60 of a millimeter.

The device which is the subject matter of this invention is based on the above considerations; one of its possible embodiments being shown by way of example in the single figure of the appended. drawing.

In the drawing, A indicates the lens body of an ordinary printing machine operating by projection and comprising two suitably conjugated windows. Secured upon this body A is an iron armature B; in addition, an electromagnet C is secured upon a massive pedestal rigidly fixed to the frame of the printing machine. Connected in the circuit of this electromagnet is an adjustable resist ing low tension current (for example 8-10 volts).

Naturally, the plane of the electromagnet and iron armature secured to the lens must be at right angles to the linear goiierings of the film to be reproduced.

It is easy to understand that when current is sent through the electromagnet C it will produce successive attractions of the armature B together with lens A which is rigidly connected thereto. The displacement of the optical center of the lens with respect to the network of the film to be reproduced will thus be obtained, each striation of said network being spread out as projected over a surface equal to the period (or interval) of I said network.

The amplitude of the movement of the lens may be selectively adjusted by means of the resistance 10 provided in the circuit.

The frequency of the alternating current will be the higher as the output of the printing machine is greater; such frequency being higher in machines with an oscillating diaphragm than in simple printing machines.

It must be noted that the lens will be brought back to its normal position after every attraction by any suitable means. Practically, such return will take place auto matically by the very elasticity of the metal of the member connecting said lens to the body of the apparatus.

Tt is to be understood that these devices may be fed with direct current if desired, in

which event a suitable vibrating or interrupting device must then be provided to produce the successive attractions of armature B.

Whatever device may be employed, its application is of particular interest in connection with such oscillating diaphragm. printing machines as are described in French Patent No. 657,910, granted December 3, 192'? to Societe Civile pour lEtude de la Photographie et de la Ginematographie en Gout eurs. In that patent, the removal of the original network is obtained by the elimination of the difiraction rays due to the passage of the light through the network of the picture to be reproduced. Such removal of the periodical network is generally connected with the appearance of marblings due to defects in the original network and particularly to index diflerences (points, lines, etc.) in the celluloid. These marblings, which are always very line and wholly different from water lines are, radically eliminated by the vibration device as described.

I claim as my invention:

In an aparatus for printing reticulated films, a projecting lens interposed between a linearly reticulated film to be copied and a blank copying film; an iron armature secured to said lens; an electromagnet associated with said armature to vibrate the same and thereby displace the optical center of the lens with relation to the network of the film to be copied, so that each striation of said network will be spread out, as projected, over a surface equal to an interval of the network; and means for imparting a very large number pf vibrations per image to said armature and 'ens.

2. Apparatus according to claim 1, in

which the means for vibrating the armature involves a source of low-tension alternating current connected to the terminals of the magnet circuit, said circuit having an adjustable resistance included therein.

In testimony whereof I afix my signature.

RUDOLPHE BERTLHQN. 

